I've been fiddling around with Cesium for about a week and found an oddity in the way dynamic ellipses/polylines update. I've got a scene where I'm rendering the globe with anywhere from 100 to 1000 'objects'. These objects consist of 3 sub-components: a billboard, an ellipse (outline, no fill for the moment), and a polyline consisting of 2 vertices/points.
I have it setup so these 'objects' update according to a clock tick(once per second) as their future position/orientation information is potentially undefined, i.e. conventional timeline/interval interface will not suffice. I initially ran into some performance issues but was able to resolve those through batch updating these objects using CZML.
On an update I move each of these 'objects' a set random distance from their current location to simulate sporadic movement. Whenever I update these 'objects' the billboards seem to update and re-draw immediately to their new positions but the ellipses and polylines disappear for a few milliseconds (more/less depending on the number of 'objects') and eventually re-appear at their new locations.
I find it odd that the billboards update/re-draw immediately but the other components have a delay, leading me to believe my code is not the direct culprit in this issue as I batch all 'object' updates into a single CZML process call. Regardless, I'm wondering if maybe there is something I'm doing wrong/could be doing better or if it is currently a limitation in the way these geometries(ellipse/polyline) are being rendered in the lower level Cesium code?